By all accounts the TD-15M is an top class woofer, but you would probably need to be prepared to wait at LEAST 6mo to a year or more for them. If you do want some, your best bet is to try and find someone from the group buy he did last year who's plans changed or decided on different woofers due to the wait involved.

In any case the dipole (OB) 15 is listed as $310, but picking an arbitrary price point for the individual drivers is not a good way to go about selecting them.

You really need to pick them based on their performance characteristics. A $20-$30 tweeter might well be better suited to a particular mid than a much more expensive one.

picking an arbitrary price point for the individual drivers is not a good way to go about selecting them.

I really don't know how to respond to this, other than to restate mt requirements.
I am looking for a 15" woofer with a moderate cost and designed to play up to 1200 Hz.
I realize that choosing one woofer for multiple projects may involve compromises.
For example, A high Qts and high Xmax would be desirable for an OB.
For the horn projects, a Moderate Qts would be better, and low Le is more important.

Take a look at Eminence Deltalite - I have a friend who has them and they are very good indeed, although they don't go very deep unless vented.

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